[LU-8019] Openlock breakage

Duplicate — Tue, 21 Nov 2017 15:50:14 +0000

Ever since ~~LU-4367~~ we have a subtle case of breakage that went unnoticed.

The breakage is two-fold:
1. When an application requests an open lock, it is granted, but cannot be used. This is because revalidate always returns 0 for open requests, but we cannot get to inode from new dentry in ll_lookup_it unless we do RPC which defeats the purpose. - Impact: Low since next to nobody cares about it.

2. When an application opens a file that is already opened for the same mode - we now do not have inode access to see that there is an open handle already, so we do a needless RPC same as above to get to the inode and then discard the filehandle right away. - The impact is a bit more, but this still could only happen if we have a lookup lock on the file first, as if we don't, we still do full lookup to get from dentry to inode.

Whamcloud Community JIRA

[LU-8019] Openlock breakage